Heat transfer label

ABSTRACT

The present invention relates to heat transfers that include silicone based heat transfer inks and digitally printed toner images, particularly for use on fabrics, apparel items, garments and accessories. The present subject matter is especially suitable for use in heat-transferable labeling or creating embellishments on polyester fabrics and garments.

CROSS REFERENCE TO RELATED APPLICATION(S)

This application claims priority to and the benefit of U.S. ProvisionalApplication No. 62/563,181 filed Sep. 26, 2017, which is incorporatedherein by reference in its entirety.

FIELD OF THE DISCLOSURE

The present subject matter relates to heat transfers that includesilicone based heat transfer inks and digitally printed toner images,particularly for use on fabrics, garments, and accessories. The presentsubject matter is especially suitable for use in heat-transferablelabeling of polyester fabrics and garments and the like.

BACKGROUND

Transfer decoration, labels, patches, tags, identification placards,embellishments and the like are widely used for a variety of differentapplications including logos, trademarks, keyboard symbols, whethernumeric, alphabetic or alphanumeric or other symbols, sports designs,logos and names, fabric and clothing design details, accents andbackgrounds, artwork of various shapes and the like. At times these arereferred to herein as designs, images and/or indicia. In someapplications, these decorative components are in the nature of heattransfers, often referred to as labels, suitable for application onfabrics, clothing and accessories that are of the performance fabricvariety exhibiting a relatively high degree of susceptibility to damageupon being subjected to heat transfer application. Such performancefabrics, clothing, apparel and accessories to be enhanced with heattransfer decorative components often concern so-called “soft goods,” aterm generally understood in the art. Examples include clothing, upperbodywear, lower bodywear, headwear, footwear, outerwear, underwear,garments, sportswear fabrics, other sheet goods, banners, flags,athletic or sport clothing, uniforms, and combinations thereof.

Performance fabrics for soft goods or the like can include thoseexhibiting stretchability, soft touch tactile characteristics, and vividcolor appearance, while being flexible in process manufacturing. Typicalsynthetic fibers suitable for inclusion in the performance fabriccategory include polyesters, polyamides, nylons, and combinations ofsuch materials with cotton and/or stretchable or resilient materialssuch as spandex or elastane or Lycra® and the like. Performance fabricsare a particular challenge for heat transfers.

SUMMARY

There are several aspects of the present subject matter which may beembodied separately or together in the devices and systems described andclaimed below. These aspects may be employed alone or in combinationwith other aspects of the subject matter described herein, and thedescription of these aspects together is not intended to preclude theuse of these aspects separately or the claiming of such aspectsseparately or in different combinations as may be set forth in theclaims appended hereto.

The present disclosure provides a heat transfer label construction forfabrics and textiles, especially for garments made of performancefabrics. The heat transfer label construction is also suitable forapparel, garments, and accessories made of cotton and cotton blends.

The printed ink design layer includes an image that is digitally printedin a laser printing process which may use toner or ink. By using asilicone based compatibility layer or additive, the image, for exampleone created by a toner based system, is fixed to enable adherence to thetransfer portion of the label construction, and in particular to a heattransfer silicone based ink layer. The compatibility layer or additivefurther allows for improved interfacing of water based inks to the heattransfer silicone ink without degrading the curing process.

In one aspect there is provided a heat transfer label that includes asupport portion having a label carrier and a release layer; and atransfer portion. The transfer portion is positioned over the supportportion release layer for transfer of the transfer portion from thesupport portion to a fabric substrate under conditions of heat andpressure.

In another embodiment, the transfer portion includes a heat transfersilicone ink layer having a first surface and a second surface, with thefirst surface being exposed to permit direct contact with a fabricsubstrate to be labeled. An image layer that includes a printed tonerlayer is provided along with a compatibility layer in contact with thesecond surface of the heat transfer silicone ink layer. Thecompatibility layer adheres the toner layer to the heat transfersilicone ink layer.

The heat transfer silicone ink layer may include a silicone ink basecomposition; a pigment; and a heat-transfer adhesion promoter being oneor more of the group that includes; (i) a hydrogen bonded silicon; (ii)an organosilane; and (iii) a metal chelate. The heat transfer siliconeink layer may further include at least one heat transfer adhesive.

The compatibility layer may be formed from a composition comprisingdecamethyltetrasiloxane, tetraethyl orthosilicate and Titanium (IV)butoxide.

In one embodiment of the present invention, the image layer furtherincludes a printed water based ink layer in addition to the image layer.

In a further aspect of the present invention, there is provided a heattransfer label that includes a support portion and a transfer portion.The transfer portion includes a heat transfer silicone ink layer whichhas a first surface and a second surface. The first surface is exposedto permit direct contact with a fabric substrate to be labeled. An imagelayer is provided and includes a printed toner layer which is in contactwith the second surface of the heat transfer silicone ink layer. Theheat transfer silicone ink layer includes a compatibility additive foradhering the image layer to the heat transfer silicone ink layer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic section view of a first embodiment of a heattransfer label assembly according to the present disclosure;

FIG. 2 is a schematic section view of a second embodiment of a heattransfer label assembly that further includes a water-based ink layeraccording to the present disclosure;

FIG. 2A provides a further schematic section view of a furtherembodiment of the heat transfer label shown in FIG. 2;

FIG. 2B illustrates a further schematic section view of a furtherembodiment of the heat transfer label shown in FIG. 2;

FIG. 3 is a schematic section view of an alternative embodiment to thatshown in FIG. 1.

DETAILED DESCRIPTION

Detailed embodiments of the present invention are disclosed herein;however, it is to be understood that the disclosed embodiments aremerely exemplary of the invention, which may be embodied in variousforms. Therefore, specific details disclosed herein are not to beinterpreted as limiting, but merely as a basis for the claims and as arepresentative basis for teaching one skilled in the art to variouslyemploy the present invention in virtually any appropriate manner.

FIG. 1 is a schematic representation of a heat transfer labelconstruction and illustrates a first embodiment that achieves securetransfer of a desired image, design and/or indicia to a fabricsubstrate. The label construction 10 includes a support portion 20 and atransfer portion 30. Support portion 20 includes a label carrier 22 anda release layer or coating 24.

The support portion 20 typically has the function of providingmechanical strength to the label assembly, allowing handling such asbeing wound up in a roll for storage, stacking, and as a label feed formechanized operations. Typical label carrier sheets are cellulosic orpolymeric film, such as heat stabilized polyethylene terephthalate(PET). The back of the film may be coated against static build up andblocking when the films are stacked against each other. In oneembodiment, the thickness of the carrier is 4 mil (100 μm). Thinnerfilms, such as those having a thickness of 50 to 75 μm, may also beused. Label carrier 22 may also be coated with one or more layers toprovide a matting effect.

Release layer 24 is coated or printed on carrier 22. In one embodiment,a release layer is coated on both sides of the carrier 22. The releaselayer also functions as a thermal release to permit the separation ofthe transfer portion 30 from the support portion 20 after the heattransfer. The release layer may be based on polymer waxes that manifestaffinity for the toners used in commercial digital printing, such as thedigital printing process of HP® Indigo® printers. Examples of suitablepolymeric waxes for the release layer include polyethylene acrylic andmethacrylic acids (EAA and EMA), polyolefin waxes that are made polar byan oxidationprocess. The release layer may also contain anti-blockingadditives, which facilitate the release layer detaching from the carrierwhen the latter is peeled during the heat transfer process. Examples ofrelease additives are polar waxes compatible with EAA, such as carnaubaand montan waxes. Other release additives includepolytetrafluoroethylene particles either in neat form or as compositeparticulates with other polyolefins. In one embodiment, the preferredcoat weight of the release layer is in the range of 0.5 to 5 gsm.

Transfer portion 30 generally includes a toner image layer 32,compatibility layer 34 overlying the toner image layer 32, and a heattransfer silicone ink layer 36. The release layer 24 receives the tonerimage layer 32. Toner image layer 32 is generally digitally printedusing a liquid electrophotographic process by which electrically-chargedliquid inks, i.e., toners, are dried and applied to the release layervia a thermal blanket. Liquid toners typically include pigments, binder,carrier solvent, dispersing agents and charge additives. The toner imagelayer 32 may be printed using HP® Indigo® digital machines in sheet-fedformat. It should be understood that other printing technologies,including a continuous or roll-to-roll format may be used.

Overlying toner image layer 32 is compatibility layer 34, which fixesthe toner image and provides an interface for the subsequently appliedheat transfer silicone based ink layer 36. In one embodiment, thecompatibility layer includes the following components:

Component Weight % Silicone fluid: decamethyltetrasiloxane 99.4% (DowCorning OS 30) Tetraethyl orthosilicate (TEOS, Aldrich) 0.5% Titanium(IV) butoxide 0.1%

The compatibility layer 34 may interact with the polymers of theunderlying toner image layer 32 to strengthen the toner layer againstwater and abrasion. For example, the compatibility layer could crosslinkthe polymers of the toner image layer if the polymers of the toner imagelayer contain chemical moieties such as hydroxyl or carboxyl groups. Inaddition, the compatibility layer may block and restrict possiblemigration of contaminants originating in the release layer from reachingthe overlying heat transfer silicone ink layer 36. Contaminants such asamines species could poison and render inactive the Pt hydrosilylationcatalyst used in curing the silicone inks.

The compatibility layer could also include silica precursors such asorganic silicates (tetraethyl orthosilicate and similar, organic silanesthat possess chemical moieties capable to reach with potential chemicaltoner functionality (hydroxyl, carboxyl). Examples of these reactivesilanes include (3-Glycidyloxypropyl)trimethoxysilane,2-(3,4-Epoxycyclohexyl)ethyltriethoxysilane). The compatibility layeralso could include silanes that are able to participate in the inhydrosililation chemical curing of the silicone ink they areinterfacing. One example of such molecule is a Trimethoxy(vinyl)silanecoupling agent.

The compatibility 34 layer may also contain colloidal silica dispersedin a fluid (solvent or water with solvent). Preferred are the silicaknown to exhibit elongated or string like particles. Examples of suchcolloidal silicas are Nissan Chemical's ORGANOSILICASOL: IPA-ST-UP andMEK-ST-UP.

The compatibility layer 34 may be coated onto the toner image layerusing a Meyer Rod (numbers 6-10) and dried in an oven at 100° C. for 1minute, resulting in a thin transparent compatibility layer that is 1gsm or less.

Overlying the compatibility layer 34 is a heat transfer silicone inklayer 36. In most applications, the heat transfer silicone ink layer 36is a white layer. In one embodiment, the heat transfer silicone inklayer is prepared in accordance with the composition described in USPatent Publication US 2015/0004336, the contents of which areincorporated herein by reference.

In one embodiment, the heat transfer silicone ink layer 36 is aheat-transfer textile ink that includes: (a) a silicone ink basecomposition; (b) a pigment; and (c) a heat-transfer adhesion promoterbeing one or more of the group that includes: (i) a hydrogen bondedsilicon; (ii) an organosilane; and (iii) a metal chelate.

Suitable pigments are known in the art, and are not further discussed indetail. They include all types of pigments, inks, tinctures, dyes,colorants and “colors”, and are included in the relevant proportionsknown in the art to provide the required image quantity and quality.Suitable pigments and dyes include but are not limited to carbon black,titanium dioxide, chromium oxide, bismuth vanadium oxide and the like.The pigments may be dispersed in the heat-transfer textile inkcomposition at the ratio of 25:75 to 70:30 to the silicone ink base.

The heat transfer silicone ink may include any proportions and/or ratiosof the heat transfer adhesion promoters listed above, such as in theamount of 0.1 wt % to 10 wt %, alternatively in the range 0.5 wt % to 5wt %.

The hydrogen bonded silicon of group (c) (i) may include

wherein m is in the range 0 and 120, and n is in the range 1 to 120.Alternatively, one or more different hydrogen bonded silicones may beincluded as the adhesion promoter.

The organosilane of group (c) (ii) may be a silane, an oligomericreaction product of the silane, or a combination thereof, in particularan alkoxysilane. Alternatively, the organosilane may include either: (i)the formula R3bSiR4; (4-b), where each is independently a monovalentorganic group; each R4 is an alkoxy group; and b is 0, 1, 2, or 3; or(ii) the formula R5cR6dSi(OR5)4-(c+d) where each R5 is independently asubstituted or unsubstituted, monovalent hydrocarbon group having atleast 1 carbon atom and each R6 contains at least one SiC bonded grouphaving an adhesion-promoting group, such as amino, epoxy, mercapto oracrylate groups, c is 0, 1 or 2, d is 1 or 2, and the sum of c+d is notgreater than 3, or a partial condensate thereof.

The organosilane may include an alkoxysilane exemplified by adialkoxysilane, such as dialkyldialkoxysilane or a trialkoxysilane, suchas an alkyltrialkoxysilane or alkenyltrialkoxysilane, or partial or fullhydrolysis products thereof, or another combination thereof.

The metal chelate of group (c)(iii) may include any suitable metal (suchas zirconium (IV) or titanium), in the form of suitable chelatecomplexes such as tetraacetylacetonate, hexafluoracetylacetonate,trifluoroacetylacetonate, tetrakis (ethyltrifluoroacetylacetonate),tetrakis (2,2,6,6-tetramethyl-heptanedionato), dibutoxybis(ethylacetonate), diisopropoxybis(2,2,6,6-tetramethyl-heptanedionato), or β-diketone complexes,including alkyl-substituted and fluoro-substituted forms thereof.Alternatively, the metal chelate is a zirconium chelate, optionallyzirconium acetyl acetonate, such as zirconium tetrakisacetylacetonate(also termed “Zr(AcAc)4”), (including alkyl-substituted andfluoro-substituted forms thereof).

The silicone ink base composition may include one or more silicone inkbase compositions known in the art, and the invention is not limitedthereto. Alternatively, the silicone ink base is as defined in US PatentPublication US 2007/141250, incorporated herein by reference.Alternatively, the silicone ink base composition for the heattransfertextile ink may include:

(A) 100 parts by weight of a liquid polydiorganosiloxane containing atleast two alkenyl radicals in each molecule,

(B) an organohydrogenpolysiloxane containing at least threesilicon-bonded hydrogen atoms in each molecule, in an amount that themolar ratio of the total number of the silicon bonded hydrogen atoms inthis ingredient to the total quantity of all alkenyl radicals iningredient (A) is from 0.5:1 to 20:1,

(C) from 5 to 50 parts by weight of a reinforcing filler, based on theamount of ingredient (A),

(D) from 0.05 to 4.5 parts by weight of a polydiorganosiloxane-polyethercopolymer containing from 5 to 50 percent by mole of the polyether,based on 100 parts by weight of the combined weight of ingredients (A),(B), and (C), and

(E) a hydrosilylation catalyst.

In one embodiment, the heat transfer silicone ink layer further includesone or more heat transfer adhesives. Such adhesives are well known forthis purpose. For example, the heat transfer adhesive may include athermoplastic polymer resin.

Curing of the heat transfer silicone ink layer is catalyzed byingredient (E), which may be a metal selected from the platinum group ofthe periodic table, or a compound of such metal. The metals includeplatinum, palladium and rhodium. Platinum and platinum compounds arepreferred due to the high activity of these catalysts in hydrosilylationreaction.

The label of FIG. 1 may be transferred to a substrate such as a fabricor textile by placing the label assembly over the substrate, applyingheat, and removing the support structure to leave the transfer portionas a lasting image on the substrate.

FIG. 2 is a schematic representation of another heat transfer labelconstruction that includes a water-based image layer in addition to atoner image layer. The label construction 110 includes a support portion120 and a transfer portion 130. Support portion 120 includes a labelcarrier 122 and a release layer or coating 124.

Transfer portion 130 is similar in most respects to transfer portion 30,the principal difference between the two is that a water based imagelayer 133 is included in the construction. The water based ink layer 133may be printed directly onto release liner 124 such that it does notoverlap toner image layer 132. Alternatively, water based ink layer 133may overlap portions of toner image layer 132. Alternatively, waterbased ink layer 133 may cover completely the toner layer 132. In thiscase the water based ink will contain the reactive ingredients need tofixate chemically the toner image. Water based ink layer 133 may beformed by screen printing, ink jet printing, gravure printing,flexographic printing, or the like.

Compatibility layer 134 overlies toner image layer 132 and water basedink layer 133 to block and restrict possible migration of contaminantsoriginating in the release layer or the water based ink from reachingthe overlying heat transfer silicone ink layer 136. Contaminants such asamines species could poison and render inactive the Pt hydrosilylationcatalyst used in curing the silicone inks. Not only are there volatilesamines used in producing the water based anionic polymer dispersions,there may also be amino group containing polymers in either the polymerbackbone or at the polymer end (i.e., polyamides, polyurethanes, etc.)

Overlying the compatibility layer 134 is heat transfer silicone inklayer 136. The label of FIG. 2 may be transferred to a substrate such asa fabric or textile by placing the label assembly over the substrate,applying heat, and removing the support structure to leave the transferportion as a lasting image on the substrate.

Attention is directed to FIG. 2A which shows an alternate embodiment ofFIG. 2 in which the water based ink layer 133 substantially covers theimage toner layer 132.

FIG. 2B is a further embodiment of the heat transfer label of thepresent invention in which the water based ink layer 133 resides on topof the carrier and/or release layer 122, 124.

FIG. 3 is a schematic representation of another heat transfer labelconstruction in which a compatibility additive is incorporated into aheat transfer silicone ink layer. The label construction 210 includes asupport portion 220 and a transfer portion 230. Support portion 220includes a label carrier 222 and a release layer or coating 224.

Toner layer 232 is printed onto release layer 224. Overlying toner layer232 is heat transfer silicone ink layer 236, which is formed from acomposition that includes a compatibility additive and a silicone basedheat transfer ink. In one embodiment, the silicone based heat transferink is prepared in accordance with the composition described in USPatent Publication US 2015/0004336, which is described in more detailabove. In one embodiment, the compatibility additive includes thefollowing components:

Component Weight %* Silicone fluid: decamethyltetrasiloxane 10.0% (DowCorning OS 30) Tetraethyl orthosilicate (TEOS, Aldrich) 0.5% Titanium(IV) butoxide 0.1% *based on the total weight of the heat transfersilicone ink layer

The compatibility additive when incorporated into the silicone basedheat transfer ink provides similar advantages as a separatecompatibility layer, and does not interfere with the siliconecrosslinking chemistry of the silicone based heat transfer ink.

Other embodiments, besides those illustrated herein, may also beemployed without departing from the scope of the present disclosure. Forexample, the label can be of a perimeter shape desired for a particularpurpose other than the generally circular or cylindrical labelsassociated with a patch or insignia, for example, taking the form of adecorative embellishment, company logo, or artwork. Other optionsinclude enhancing the flexibility of the label or the like by minimizingthe thickness and area covered by the second barrier layer, therebyproviding improved label performance in terms of being able to betterfollow bendability or flow of the substrate to which the label isattached, such as fabric or clothing.

It will be understood that the embodiments described above areillustrative of some of the applications of the principles of thepresent subject matter. Numerous modifications may be made by thoseskilled in the art without departing from the spirit and scope of theclaimed subject matter, including those combinations of features thatare individually disclosed or claimed herein. For these reasons, thescope hereof is not limited to the above description but is as set forthin the following claims, and it is understood that claims may bedirected to the features hereof, including as combinations of featuresthat are individually disclosed or claimed herein.

1. A heat transfer label comprising: a support portion having a labelcarrier and a release layer; and a transfer portion, said transferportion being positioned over the support portion release layer fortransfer of the transfer portion from the support portion to a fabricsubstrate under conditions of heat and pressure, the transfer portioncomprising: a heat transfer silicone ink layer having a first surfaceand a second surface, the first surface being exposed to permit directcontact with a fabric substrate to be labeled; an image layer comprisinga printed toner layer; and a compatibility layer in contact with thesecond surface of the heat transfer silicone ink layer, wherein thecompatibility layer adheres the toner layer to the heat transfersilicone ink layer.
 2. The heat transfer label of claim 1, wherein theheat transfer silicone ink layer comprises: silicone ink basecomposition; a pigment; and a heat-transfer adhesion promoter being oneor more of the group comprising: a hydrogen bonded silicon; anorganosilane; and a metal chelate.
 3. The heat transfer label of claim2, wherein the heat transfer silicone ink layer further comprises atleast one heat transfer adhesive.
 4. The heat transfer label of claim 2,wherein the compatibility layer is transparent.
 5. The heat transferlabel of claim 2, wherein the compatibility layer has a thickness ofabout 1 gsm.
 6. The heat transfer label of claim 2, wherein thecompatibility layer is formed from a composition comprisingdecamethyltetrasiloxane, tetraethyl orthosilicate and Titanium (IV)butoxide. Reactive silanes and colloidal silica.
 7. The heat transferlabel of claim 2, wherein the image layer further comprises a printedwater based ink layer.
 8. A heat transfer label comprising: a supportportion having a label carrier and a release layer; and a transferportion, the transfer portion being positioned over said support portionrelease layer for transfer of the transfer portion from the supportportion to a fabric substrate under conditions of heat and pressure, thetransfer portion comprising: a heat transfer silicone ink layer having afirst surface and a second surface, the first surface being exposed topermit direct contact with a fabric substrate to be labeled; and animage layer comprising a printed toner layer, the image layer in contactwith the second surface of the heat transfer silicone ink layer; whereinthe heat transfer silicone ink layer comprises a compatibility additivefor adhering the toner layer to the heat transfer silicone ink layer. 9.The heat transfer label of claim 8, wherein the heat transfer siliconeink layer comprises: silicone ink base composition; a pigment; and aheat-transfer adhesion promoter being one or more of the groupcomprising: a hydrogen bonded silicon; an organosilane; and a metalchelate; and a compatibility additive comprisingdecamethyltetrasiloxane, tetraethyl orthosilicate and Titanium (IV)butoxide.
 10. The heat transfer label of claim 8, wherein the heattransfer silicone ink layer further comprises at least one heat transferadhesive.
 11. The heat transfer label of any one of claims 8, whereinthe image layer further comprises a printed water based ink layer.
 12. Aheat transfer label, comprising; a water based ink; a toner image layer;and wherein the toner image layer is substantially covered by the waterbased ink.